2D WS2-Based Single-Electrode Triboelectric Nanogenerator for Power Generation and Motion Sensing

We report on the fabrication of a tungsten disulphide (WS2) nanosheet (NS)-based single-electrode triboelectric nanogenerator (STENG) for possible application in nanoscale power generators and motion sensors. STENG devices in flexible and wearable modes were fabricated with chemically exfoliated WS2 NS-coated cellulose paper and silk textile as active layers. The triboelectric characteristics of the devices comprising a different counter triboelectric layer such as metallic aluminium (Al), polytetrafluoroethylene (PTFE), etc., confirm that WS2 has strong affinity towards donating electrons to the counter layer. The STENG device with the WS2-PTFE pair is found to exhibit the highest open-circuit voltage (V-oc) of similar to 11.02 V amongst all devices. The device delivers maximum output power of similar to 1.7 mu W and can accumulate similar to 2 nC of charge in a storing capacitor within 3 s of impact. The adequate response of the STENG to small impacts with an estimated sensitivity of 0.2VN(-1) (0.15 V kPa(-1)) indicates the possible application of the device as force sensors. Apart from that, upon attaching the flexible and wearable STENG on different parts of the human body, the device exhibits the scope for motion sensing application. The biomechanical actions like finger, neck and hand movement at different angles can generate different output signals in terms of voltage values and signal shape. The present study demonstrates the possible scope of WS2-based TENG for tactile, motion sensing applications and may pave the path for futuristic self-powered sensors. [GRAPHICS] .